terclim by ICS banner
IVES 9 IVES Conference Series 9 A better understanding of the climate effect on anthocyanin accumulation in grapes using a machine learning approach

A better understanding of the climate effect on anthocyanin accumulation in grapes using a machine learning approach

Abstract

The current climate changes are directly threatening the balance of the vineyard at harvest time. The maturation period of the grapes is shifted to the middle of the summer, at a time when radiation and air temperature are at their maximum. In this context, the implementation of corrective practices becomes problematic. Unfortunately, our knowledge of the climate effect on the quality of different grape varieties remains very incomplete to guide these choices. During the Innovine project, original experiments were carried out on Syrah to study the combined effects of normal or high air temperature and varying degrees of exposure of the berries to the sun. Berries subjected to these different conditions were sampled and analyzed throughout the maturation period. Several quality characteristics were determined, including anthocyanin content. The objective of the experiments was to investigate which climatic determinants were most important for anthocyanin accumulation in the berries. Temperature and irradiance data, observed over time with a very thin discretization step, are called functional data in statistics. We developed the procedure SpiceFP (Sparse and Structured Procedure to Identify Combined Effects of Functional Predictors) to explain the variations of a scalar response variable (a grape berry quality variable for example) by two or three functional predictors (as temperature and irradiance) in a context of joint influence of these predictors. Particular attention was paid to the interpretability of the results. Analysis of the data using SpiceFP identified a negative impact of morning combinations of low irradiance (lower than about 100 μmol m−2 s−1 or 45 μmol m−2 s−1 depending on the advanced-delayed state of the berries) and high temperature (higher than 25oC). A slight difference associated with overnight temperature occurred between these effects identified in the morning.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Girault Gnanguenon Guesse1, Patrice Loisel1, Bénedicte Fontez1, Nadine Hilgert1 and Thierry Simonneau2

1MISTEA, Université Montpellier, INRAE, Institut Agro, Montpellier, France
2LEPSE, Université Montpellier, INRAE, Institut Agro, Montpellier, France

Contact the author

Keywords

machine learning, anthocyanin, temperature, irradiance, SpiceFP

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Diversity of leaf functioning under water deficit in a large grapevine panel: high throughput phenotyping and genetic analyses

Water resource is a major limiting factor impacted by climate change that threatens grapevine production and quality. Understanding the ecophysiological mechanisms involved in the response to water deficit is crucial to select new varieties more drought tolerant. A major bottleneck that hampers such advances is the lack of methods for measuring fine functioning traits on thousands of plants as required for genetic analyses. This study aimed at investigating how water deficit affects the trade-off between carbon gains and water losses in a large panel representative of the Vitis vinifera genetic diversity. 250 genotypes were grown under 3 watering scenarios (well-watered, moderate and severe water deficit) in a high-throughput phenotyping platform.

Freeze-thaw temperature oscillations promote increased differential gene expression during grapevine bud dormancy

In northern cold climate conditions, chilling requirement fulfillment in dormant grapevine buds is slowed or stopped by subzero temperatures impacting the transcriptional processes needed to complete chilling requirement. Cabernet Franc and Reisling in Geneva, NY were used to determine the impact of natural oscillating temperatures on grapevine bud transcriptional activity during light and dark periods of a two-week period in January with fluctuating diurnal winter temperatures. Cabernet Franc and Reisling bud samples were collected at 32 time points during the natural vineyard temperature cycle at 6:00 (dark), 14:00 (light) and 18:00 (dark) hours) to monitor gene expression in consecutive freezing and non-freezing temperature oscillations. Genotype, light and dark, and temperature oscillations conditions were explored.

Assessment of plant water consumption rates under climate change conditions through an automated modular platform

The impact of climate change is noticeable in the present weather, making water scarcity the most immediate mediator reducing the performance and viability of crops, including grapevine (Vitis vinifera L.). The present study developed a system (hardware, firmware, and software) for the determination of plant water use through changes in weight through a period. The aim is to measure the differences in grapevine water consumption in response to climate change (+4oC and 700 ppm) under controlled conditions. The results reveal a correlation between daily plant consumption rates and reference evapotranspiration (ETo).

Teinturier grapes: Valorization as a source of high-value compounds for the Chilean food industry

The agri-food industry is constantly searching for ingredients of high functional value, healthy and of natural origin. One species of particular interest is Vitis vinifera, due to its recognized antioxidant potential. Among the grape varieties, one group possesses these antioxidant compounds not only in the skin, but also in its pulp: Teinturier. The red grape has traditionally been used for color correction purposes in winemaking, however, its high antioxidant content transforms it into a raw material of high potential for new formulations of ingredients and foods for the health and wellness market.

A generic method to analyze vine water deficit continuously

In the context of global warming, water scarcity is becoming an increasing issue worldwide. However, the reference method to characterize vine water deficit is based on water potential measurement, which is a destructive and discontinuous method. The current climatic context emphasizes the need for more precise and more continuous vineyard water use measurements in order to optimize irrigation and vine water deficit monitoring.